A wastewater bacterium Bacillus sp. KUJM2 acts as an agent for remediation of potentially toxic elements and promoter of plant (Lens culinaris) growth

Monojit MONDAL, Jayanta Kumar BISWAS, Yiu Fai TSANG, Binoy SARKAR, Dibyendu SARKAR, Mahendra RAI, Santosh Kumar SARKAR, Peter S. HOODA

Research output: Contribution to journalArticle

Abstract

This study investigated the role of an allochthonous Gram-positive wastewater bacterium (Bacillus sp. KUJM2) selected through rigorous screening, for the removal of potentially toxic elements (PTEs; As, Cd, Cu, Ni) and promotion of plant growth under PTE-stress conditions. The dried biomass of the bacterial strain removed PTEs (5 mg L⁻¹) from water by 90.17–94.75 and 60.4–81.41%, whereas live cells removed 87.15–91.69 and 57.5–78.8%, respectively, under single-PTE and co-contaminated conditions. When subjected to a single PTE, the bacterial production of indole-3-acetic acid (IAA) reached the maxima with Cu (67.66%) and Ni (64.33%), but Cd showed an inhibitory effect beyond 5 mg L⁻¹ level. The multiple-PTE treatment induced IAA production only up to 5 mg L⁻¹ beyond which inhibition ensued. Enhanced germination rate, germination index and seed production of lentil plant (Lens culinaris) under the bacterial inoculation indicated the plant growth promotion potential of the microbial strain. Lentil plants, as a result of bacterial inoculation, responded with higher shoot length (7.1–27.61%), shoot dry weight (18.22–36.3%) and seed production (19.23–29.17%) under PTE-stress conditions. The PTE uptake in lentil shoots decreased by 67.02–79.85% and 65.94–78.08%, respectively, under single- and multiple-PTE contaminated conditions. Similarly, PTE uptake was reduced in seeds up to 72.82–86.62% and 68.68–85.94%, respectively. The bacteria-mediated inhibition of PTE translocation in lentil plant was confirmed from the translocation factor of the respective PTEs. Thus, the selected bacterium (Bacillus sp. KUJM2) offered considerable potential as a PTE remediating agent, plant growth promoter and regulator of PTE translocation curtailing environmental and human health risks. Copyright © 2019 Published by Elsevier Ltd.
Original languageEnglish
Pages (from-to)439-452
JournalChemosphere
Volume232
Early online date22 May 2019
DOIs
Publication statusPublished - Oct 2019

Fingerprint

Lens Plant
Poisons
Bacilli
Waste Water
Remediation
Chemical elements
Bacillus
Lenses
Bacteria
Wastewater
remediation
Seed
wastewater
bacterium
Growth
Seeds
Acetic acid
translocation
Germination
shoot

Citation

Mondal, M., Biswas, J. K., Tsang, Y. F., Sarkar, B., Sarkar, D., Rai, M., . . . Hooda, P. S. (2019). A wastewater bacterium Bacillus sp. KUJM2 acts as an agent for remediation of potentially toxic elements and promoter of plant (Lens culinaris) growth. Chemosphere, 232, 439-452. doi: 10.1016/j.chemosphere.2019.05.156

Keywords

  • Bacillus sp.
  • Potentially toxic elements
  • IAA production
  • Plant growth enhancement
  • Bioremediation
  • Environmental management